LEDBrick Project - DIY pendant w/ pucks
- Thread starter theatrus
- Start date
theatrus
100-mile-commuter
Had to build a second revision of the BLE PWM board:
Mostly wrong pin outs (SWDIO and SWCLK reversed, Vin and Vcc on the MCP16311 reversed), along with some bad footprints (extended pads on the PWM controller, totally wrong fan header, and some missing guide holes for connectors). There is also a tweak to the fan power circuit to avoid some of the brushless motor transients.
Mostly wrong pin outs (SWDIO and SWCLK reversed, Vin and Vcc on the MCP16311 reversed), along with some bad footprints (extended pads on the PWM controller, totally wrong fan header, and some missing guide holes for connectors). There is also a tweak to the fan power circuit to avoid some of the brushless motor transients.
theatrus
100-mile-commuter
Long awaited updated, when other projects and life get in the way. I've been using the LEDBrick pendants with several months now, but never got around to fully integrating anymore more than on/off control.
I've finished initial firmware for the LEDBrick Bluetooth Low Energy PWM controller, which isn't overly specific to this project and could be integrated into anything else needing 8-16 PWM channels and fan power/monitoring.
Features:
- 8 PWM channel dimming (though 16 total could be brought out to a header)
- 24V power input
- 12V fan power output with voltage control, PWM control, and tachometer readback
- nRF51 based Cortex-M0 + Bluetooth Low Energy stack (phone or PC control and monitoring of each channel and fan)
Apologies for the crooked caps - I bumped the board just out of reflow and some of the more massive components shifted.
Currently two characteristics are supported (LED and FAN):
I'm going to be updating the GitHub pages in a few days, stay tuned:
https://github.com/theatrus/ledbrick
I've finished initial firmware for the LEDBrick Bluetooth Low Energy PWM controller, which isn't overly specific to this project and could be integrated into anything else needing 8-16 PWM channels and fan power/monitoring.
Features:
- 8 PWM channel dimming (though 16 total could be brought out to a header)
- 24V power input
- 12V fan power output with voltage control, PWM control, and tachometer readback
- nRF51 based Cortex-M0 + Bluetooth Low Energy stack (phone or PC control and monitoring of each channel and fan)
Apologies for the crooked caps - I bumped the board just out of reflow and some of the more massive components shifted.
Currently two characteristics are supported (LED and FAN):
I'm going to be updating the GitHub pages in a few days, stay tuned:
https://github.com/theatrus/ledbrick
Last edited:
theatrus
100-mile-commuter
There is no built in feedback, but it's fixed by low power resistor. The actual control is handled by duty cycle (PWM)
theatrus
100-mile-commuter
Great question! I'll have to go calculate it out, so the following are ballparks. Some parts are bought in much higher quantity than I need.
The driver, in parts, is about $4 a channel (x8). The emitter is relatively expensive, especially due to the 4x$30 Luxeon UV LEDs. The small run of metal core PCBs ended up at about $9 a unit, but I'll have to dig the cost of LEDs.
Heatsink about $12 (HeatsinkUSA), and odds and ends from McMaster means about another $5 in mechanical parts. Fan was $10.
theatrus
100-mile-commuter
Design files (schematic, gerber, drill, board images, basic BOM) and firmware have been updated on GitHub:
https://github.com/theatrus/ledbrick
https://github.com/theatrus/ledbrick
monkeyruler90
New member
wow, looks awesome. great build thread!
theatrus
100-mile-commuter
I spent some time mocking up a case for the lights. I'm not totally happy with the side panels yet (more on that later), but a quick walk through the process:
Cutting the clear pieces on the laser:
The raw bits after cutting. The thinnest piece warped a bit from the cutting heat.
Putting the spacers on the bottom panel:
(Not pictured: cutting the side panels)
The basic box structure of the light cover. Far too many large holes and not optimized airflow. Also a smidgen too tall:
Cutting the clear pieces on the laser:
The raw bits after cutting. The thinnest piece warped a bit from the cutting heat.
Putting the spacers on the bottom panel:
(Not pictured: cutting the side panels)
The basic box structure of the light cover. Far too many large holes and not optimized airflow. Also a smidgen too tall:
theatrus
100-mile-commuter
The finish product from above. See what I said about a smidgen too tall? 
A detail side shot:
You'll notice that this is asymmetric - the idea was to port some of the air from the downward firing fan across the surface of the LEDs, which isn't super optimal for an air path and isn't well ducted, but appears to provide some actual flow.
The new LED cover:
A detail side shot:
You'll notice that this is asymmetric - the idea was to port some of the air from the downward firing fan across the surface of the LEDs, which isn't super optimal for an air path and isn't well ducted, but appears to provide some actual flow.
The new LED cover:
theatrus
100-mile-commuter
Look into the A6211. O2Surplus happens to have a large cash of them at the moment. about the only way you'll get them. He ordered a few hundred a while back for assorted projects. Shoot him a PM, I'm sure he can spare you a few.
I have, and I have some. But no need to drive to 3A and the shunt less current sense of the LM3414 is nice.
